A conventional initiator of this kind includes a pair of electrode pins held together via an insulating member; a bridge wire connected to the electrode pins and generating heat upon energization; an ignitable material (an initiating explosive) which is ignited through exposure to heat generated by the bridge wire; and a casing (capsule) for accommodating the bridge wire and the ignitable material in a sealed condition, as disclosed in, for example, Japanese Patent Application Laid-Open (kokai) No. 11-301402.
In the above-mentioned conventional initiator, the direction in which the electrode pins extend (hereinafter called the “extending direction”) and the flame propagation direction of the ignitable material (initiating explosive) are substantially the same (substantially aligned with each other). As a result, the initiator provides poor diversity in its manner of use and may, in some cases, involve low propagation efficiency of flame energy to a gas-generating material contained in an inflator or poor workability in terms of connection of a connector to the electrode pins.